Mae, who was the first surrogate mother sea otter to raise a pup on exhibit at the Monterey Bay Aquarium, has died. She was 11.

Mae died on Saturday after the onset of a seizure disorder whose cause is still unknown.

Mae was rescued as a two-day-old pup near Santa Cruz in April 2001, and raised by the aquarium's Sea Otter Research and Conservation program team. She joined the sea otter exhibit in December 2001 after it became clear that she was not acquiring the skills she needed to survive in the wild.

In 2010, she became the first surrogate mother otter to raise a pup on exhibit at the aquarium. The pup, Kit, is now living at SeaWorld San Diego. Mae served as a surrogate mother to five pups.

The sea otter exhibit is currently closed for renovations and will reopen in mid-March. Exhibit otters Rosa and Abby and are being housed behind the scenes.

Mae, nicknamed "Mayhem" by her caretakers, was a vocal and feisty animal who would make direct eye contact with and stick her tongue out at trainers when displeased, according to staff. But she was also an enthusiastic partner in training sessions, said Chris DeAngelo, associate curator of marine mammals.

"Mae definitely knew the most behaviors of any of our otters and was wonderful to teach new behaviors," DeAngelo said. "We'll all miss her terribly."